LU-10391 socklnd: use interface index to track local addr

[fs/lustre-release.git] / lnet / lnet / lib-socket.c

diff --git a/lnet/lnet/lib-socket.c b/lnet/lnet/lib-socket.c
index 7c7406c..b801b47 100644 (file)
--- a/lnet/lnet/lib-socket.c
+++ b/lnet/lnet/lib-socket.c
@@ -39,6 +39,7 @@
 /* For sys_open & sys_close */
 #include <linux/syscalls.h>
 #include <net/sock.h>
+#include <linux/inetdevice.h>
 
 #include <libcfs/libcfs.h>
 #include <lnet/lib-lnet.h>
@@ -175,10 +176,44 @@ lnet_sock_read(struct socket *sock, void *buffer, int nob, int timeout)
 }
 EXPORT_SYMBOL(lnet_sock_read);
 
+int choose_ipv4_src(__u32 *ret, int interface, __u32 dst_ipaddr, struct net *ns)
+{
+       struct net_device *dev;
+       struct in_device *in_dev;
+       int err;
+       DECLARE_CONST_IN_IFADDR(ifa);
+
+       rcu_read_lock();
+       dev = dev_get_by_index_rcu(ns, interface);
+       err = -EINVAL;
+       if (!dev || !(dev->flags & IFF_UP))
+               goto out;
+       in_dev = __in_dev_get_rcu(dev);
+       if (!in_dev)
+               goto out;
+       err = -ENOENT;
+       in_dev_for_each_ifa_rcu(ifa, in_dev) {
+               if (*ret == 0 ||
+                   ((dst_ipaddr ^ ntohl(ifa->ifa_local))
+                    & ntohl(ifa->ifa_mask)) == 0) {
+                       /* This address at least as good as what we
+                        * already have
+                        */
+                       *ret = ntohl(ifa->ifa_local);
+                       err = 0;
+               }
+       }
+       endfor_ifa(in_dev);
+out:
+       rcu_read_unlock();
+       return err;
+}
+EXPORT_SYMBOL(choose_ipv4_src);
+
 static struct socket *
-lnet_sock_create(__u32 local_ip, int local_port, struct net *ns)
+lnet_sock_create(int interface, struct sockaddr *remaddr,
+                int local_port, struct net *ns)
 {
-       struct sockaddr_in  locaddr;
        struct socket      *sock;
        int                 rc;
        int                 option;
@@ -201,12 +236,25 @@ lnet_sock_create(__u32 local_ip, int local_port, struct net *ns)
                goto failed;
        }
 
-       if (local_ip != 0 || local_port != 0) {
-               memset(&locaddr, 0, sizeof(locaddr));
+       if (interface >= 0 || local_port != 0) {
+               struct sockaddr_in locaddr = {};
+
                locaddr.sin_family = AF_INET;
+               locaddr.sin_addr.s_addr = INADDR_ANY;
+               if (interface >= 0) {
+                       struct sockaddr_in *sin = (void *)remaddr;
+                       __u32 ip;
+
+                       rc = choose_ipv4_src(&ip,
+                                            interface,
+                                            ntohl(sin->sin_addr.s_addr),
+                                            ns);
+                       if (rc)
+                               goto failed;
+                       locaddr.sin_addr.s_addr = htonl(ip);
+               }
+
                locaddr.sin_port = htons(local_port);
-               locaddr.sin_addr.s_addr = (local_ip == 0) ?
-                                         INADDR_ANY : htonl(local_ip);
 
                rc = kernel_bind(sock, (struct sockaddr *)&locaddr,
                                 sizeof(locaddr));
@@ -303,12 +351,12 @@ lnet_sock_getbuf(struct socket *sock, int *txbufsize, int *rxbufsize)
 EXPORT_SYMBOL(lnet_sock_getbuf);
 
 struct socket *
-lnet_sock_listen(__u32 local_ip, int local_port, int backlog, struct net *ns)
+lnet_sock_listen(int local_port, int backlog, struct net *ns)
 {
        struct socket *sock;
        int rc;
 
-       sock = lnet_sock_create(local_ip, local_port, ns);
+       sock = lnet_sock_create(-1, NULL, local_port, ns);
        if (IS_ERR(sock)) {
                rc = PTR_ERR(sock);
                if (rc == -EADDRINUSE)
@@ -327,7 +375,7 @@ lnet_sock_listen(__u32 local_ip, int local_port, int backlog, struct net *ns)
 }
 
 struct socket *
-lnet_sock_connect(__u32 local_ip, int local_port,
+lnet_sock_connect(int interface, int local_port,
                  __u32 peer_ip, int peer_port,
                  struct net *ns)
 {
@@ -335,15 +383,16 @@ lnet_sock_connect(__u32 local_ip, int local_port,
        struct sockaddr_in srvaddr;
        int rc;
 
-       sock = lnet_sock_create(local_ip, local_port, ns);
-       if (IS_ERR(sock))
-               return sock;
-
        memset(&srvaddr, 0, sizeof(srvaddr));
        srvaddr.sin_family = AF_INET;
        srvaddr.sin_port = htons(peer_port);
        srvaddr.sin_addr.s_addr = htonl(peer_ip);
 
+       sock = lnet_sock_create(interface, (struct sockaddr *)&srvaddr,
+                               local_port, ns);
+       if (IS_ERR(sock))
+               return sock;
+
        rc = kernel_connect(sock, (struct sockaddr *)&srvaddr,
                            sizeof(srvaddr), 0);
        if (rc == 0)
@@ -355,8 +404,8 @@ lnet_sock_connect(__u32 local_ip, int local_port,
         * port... */
 
        CDEBUG_LIMIT(rc == -EADDRNOTAVAIL ? D_NET : D_NETERROR,
-                    "Error %d connecting %pI4h/%d -> %pI4h/%d\n", rc,
-                    &local_ip, local_port, &peer_ip, peer_port);
+                    "Error %d connecting %d -> %pI4h/%d\n", rc,
+                    local_port, &peer_ip, peer_port);
 
        sock_release(sock);
        return ERR_PTR(rc);